@article{BiehlDreslerReifetal.2011,
  author    = {Biehl, Stefanie C. and Dresler, Thomas and Reif, Andreas and Scheuerpflug, Peter and Deckert, J{\"u}rgen and Herrmann, Martin J.},
  title     = {Dopamine Transporter (DAT1) and Dopamine Receptor D4 (DRD4) Genotypes Differentially Impact on Electrophysiological Correlates of Error Processing},
  series = {PLoS One},
  volume    = {6},
  journal   = {PLoS One},
  number    = {12},
  doi       = {10.1371/journal.pone.0028396},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-137930},
  pages     = {e28396},
  year      = {2011},
  abstract  = {Recent studies as well as theoretical models of error processing assign fundamental importance to the brain's dopaminergic system. Research about how the electrophysiological correlates of error processing—the error-related negativity (ERN) and the error positivity (Pe)—are influenced by variations of common dopaminergic genes, however, is still relatively scarce. In the present study, we therefore investigated whether polymorphisms in the DAT1 gene and in the DRD4 gene, respectively, lead to interindividual differences in these error processing correlates. One hundred sixty participants completed a version of the Eriksen Flanker Task while a 26-channel EEG was recorded. The task was slightly modified in order to increase error rates. During data analysis, participants were split into two groups depending on their DAT1 and their DRD4 genotypes, respectively. ERN and Pe amplitudes after correct responses and after errors as well as difference amplitudes between errors and correct responses were analyzed. We found a differential effect of DAT1 genotype on the Pe difference amplitude but not on the ERN difference amplitude, while the reverse was true for DRD4 genotype. These findings are in line with predictions from theoretical models of dopaminergic transmission in the brain. They furthermore tie results from clinical investigations of disorders impacting on the dopamine system to genetic variations known to be at-risk genotypes.},
  language  = {en}
}
@article{KopfDreslerReichertsetal.2013,
  author    = {Kopf, Juliane and Dresler, Thomas and Reicherts, Philipp and Herrmann, Martin J. and Reif, Andreas},
  title     = {The Effect of Emotional Content on Brain Activation and the Late Positive Potential in a Word n-back Task},
  series = {PLoS ONE},
  journal   = {PLoS ONE},
  doi       = {10.1371/journal.pone.0075598},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-96687},
  year      = {2013},
  abstract  = {Introduction There is mounting evidence for the influence of emotional content on working memory performance. This is particularly important in light of the emotion processing that needs to take place when emotional content interferes with executive functions. In this study, we used emotional words of different valence but with similar arousal levels in an n-back task. Methods We examined the effects on activation in the prefrontal cortex by means of functional near-infrared spectroscopy (fNIRS) and on the late positive potential (LPP). FNIRS and LPP data were examined in 30 healthy subjects. Results Behavioral results show an influence of valence on the error rate depending on the difficulty of the task: more errors were made when the valence was negative and the task difficult. Brain activation was dependent both on the difficulty of the task and on the valence: negative valence of a word diminished the increase in activation, whereas positive valence did not influence the increase in activation, while difficulty levels increased. The LPP also differentiated between the different valences, and in addition was influenced by the task difficulty, the more difficult the task, the less differentiation could be observed. Conclusions Summarized, this study shows the influence of valence on a verbal working memory task. When a word contained a negative valence, the emotional content seemed to take precedence in contrast to words containing a positive valence. Working memory and emotion processing sites seemed to overlap and compete for resources even when words are carriers of the emotional content.},
  language  = {en}
}